title: The association of body mass index, waist and hip circumference, and waist-hip ratio with Chlamydia pneumoniae IgG antibodies and high-sensitive C-reactive protein at 31 years of age in Northern Finland Birth Cohort 1966.
abstract: BACKGROUND
  Viruses and bacteria like Chlamydia pneumoniae and Helicobacter pylori have been suggested to have a role in pathogenesis of overweight and obesity.
  
  
  OBJECTIVE
  We studied whether C. pneumoniae-specific IgG antibodies are associated with elevated body mass index (BMI), waist and hip circumference, and/or waist-hip ratio (WHR), and whether the risk is more pronounced in the simultaneous presence of an ongoing inflammation as measured by elevated high-sensitive C-reactive protein (hsCRP) levels.
  
  
  METHODS
  Our study population was derived from the Northern Finland Birth Cohort 1966 (NFBC1966), a general population sample of 12,058 live-born children. This cross-sectional study consisted of 5044 persons at 31 years of age. Serum C. pneumoniae IgG titers were measured by microimmunofluorescence test, and hsCRP levels by immunoenzymometric assay.
  
  
  RESULTS
  C. pneumoniae IgG positivity (titer ≥ 32), both alone and jointly with elevated hsCRP (≥ 1.64 mg l(-1), an upper quartile), was found to significantly associate with elevated BMI in the whole study population and with elevated hip and waist circumference in women, yet no association with WHR was seen. The analyses were adjusted for sex (when appropriate), smoking, socioeconomic position, glucose, insulin, high- and low-density lipoprotein cholesterols, triglycerides, leukocytes and pulse pressure.
  
  
  CONCLUSIONS
  These findings suggest that especially in women, persistent C. pneumoniae infection may be associated with overweight/obesity, independently of more traditional risk factors.
authors.affiliation: Institute of Biomedicine, Department of Physiology, University of Oulu, Oulu, Finland. taina.lajunen@oulu.fi
authors.forename: T
authors.initials: T
authors.lastname: Lajunen
authors.forename: A
authors.initials: A
authors.lastname: Bloigu
authors.forename: M
authors.initials: M
authors.lastname: Paldanius
authors.forename: A
authors.initials: A
authors.lastname: Pouta
authors.forename: J
authors.initials: J
authors.lastname: Laitinen
authors.forename: A
authors.initials: A
authors.lastname: Ruokonen
authors.forename: A-L
authors.initials: AL
authors.lastname: Hartikainen
authors.forename: M
authors.initials: M
authors.lastname: Savolainen
authors.forename: K-H
authors.initials: KH
authors.lastname: Herzig
authors.forename: M
authors.initials: M
authors.lastname: Leinonen
authors.forename: P
authors.initials: P
authors.lastname: Saikku
authors.forename: M-R
authors.initials: MR
authors.lastname: Järvelin
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism*; D023521:Chlamydophila Infections / Q000097:blood / Q000150:complications* / Q000382:microbiology; D016993:Chlamydophila pneumoniae / Q000276:immunology / Q000302:isolation & purification*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D005387:Finland / Q000453:epidemiology; D005455:Fluorescent Antibody Technique; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008019:Life Style; D008297:Male; D009765:Obesity / Q000097:blood* / Q000453:epidemiology / Q000382:microbiology* / Q000473:pathology; D018570:Risk Assessment; D012494:Sampling Studies; D011795:Surveys and Questionnaires; D055105:Waist Circumference; D049629:Waist-Hip Ratio
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D002097:C-Reactive Protein